Service Manual

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Policy-based Routing (PBR)
Policy-based Routing (PBR) allows a switch to make routing decisions based on policies applied to an interface.
This chapter covers the following topics:
• Overview
• Implementing Policy-based Routing with Dell Networking OS
• Conguration Task List for Policy-based Routing
• Sample Conguration
Overview
When a router receives a packet it normally decides where to forward it based on the destination address in the packet, which is
used to look up an entry in a routing table. However, in some cases, there may be a need to forward the packet based on other
criteria: size, source, protocol type, destination, etc. For example, a network administrator might want to forward a packet that uses
TCP across a dierent next-hop than packets using ICMP. In these situations, you can congure a switch route packets according to
a policy applied to interfaces.
Rules for PBR can also be a combination of things:
When the packet comes from this source and wants to go to that destination then route it to this next-hop or onto that specic
interface. This permits routing over dierent links or towards dierent networks even while the destination is the same but
depending on where the packet originates.
Policy-based Routing (PBR)
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